#region Using Directives and Copyright Notice

// Copyright (c) 2007-2010, Computer Consultancy Pty Ltd
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above copyright
//       notice, this list of conditions and the following disclaimer in the
//       documentation and/or other materials provided with the distribution.
//     * Neither the name of the Computer Consultancy Pty Ltd nor the
//       names of its contributors may be used to endorse or promote products
//       derived from this software without specific prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
// ARE DISCLAIMED. IN NO EVENT SHALL COMPUTER CONSULTANCY PTY LTD BE LIABLE 
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 
// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
// DAMAGE.

using System;
using System.ComponentModel;
using System.Collections.Generic;
using System.Text;
using System.Reflection;

#endregion

namespace Interlace.Binding
{
    class PropertyBinderModel : Interlace.Binding.IBinderModel
    {
        private string _propertyName;

        object _boundTo;
        Type _boundToType;

        bool _ignoreChangedEvent;

        private BinderController _controller;

        public PropertyBinderModel(string propertyName)
        {
            _propertyName = propertyName;

            _boundTo = null;

            _ignoreChangedEvent = false;
        }

        public BinderController Controller
        {
            set { _controller = value; }
        }

        public string GetDescriptionForTracing()
        {
            if (_boundTo == null) return string.Format(
                "Property \"{0}\" of null", _propertyName);

            return string.Format("Property \"{0}\" of \"{1}\", type \"{2}\"",
                _propertyName, _boundTo, _boundToType.Name);
        }

        private void ConnectEvents()
        {
            EventInfo changeEvent = _boundToType.GetEvent(_propertyName + "Changed");

            if (changeEvent != null)
            {
                changeEvent.AddEventHandler(_boundTo, new EventHandler(ChangedEventHandler));
            }
            else
            {
                if (_boundTo is INotifyPropertyChanged)
                {
                    INotifyPropertyChanged notifier = _boundTo as INotifyPropertyChanged;

                    notifier.PropertyChanged += new PropertyChangedEventHandler(PropertyChangedEventHandler);
                }
            }
        }

        private void DisconnectEvents()
        {
            EventInfo changeEvent = _boundToType.GetEvent(_propertyName + "Changed");

            if (changeEvent != null)
            {
                changeEvent.RemoveEventHandler(_boundTo, new EventHandler(ChangedEventHandler));
            }
            else
            {
                if (_boundTo is INotifyPropertyChanged)
                {
                    INotifyPropertyChanged notifier = _boundTo as INotifyPropertyChanged;

                    notifier.PropertyChanged -= new PropertyChangedEventHandler(PropertyChangedEventHandler);
                }
            }
        }

        public void ConnectBoundToObject(object boundTo)
        {
            if (_boundTo != null)
            {
                DisconnectEvents();
            }

            _boundTo = boundTo;
            _boundToType = boundTo.GetType();

            ConnectEvents();

            _controller.OnModelModified();
        }

        public void DisconnectBoundToObject()
        {
            if (_boundTo != null)
            {
                DisconnectEvents();
            }

            _boundTo = null;
            _boundToType = null;

            _controller.OnModelModified();
        }

        private void ChangedEventHandler(object sender, EventArgs e)
        {
            if (_ignoreChangedEvent) return;

            _controller.OnModelModified();
        }

        void PropertyChangedEventHandler(object sender, PropertyChangedEventArgs e)
        {
            if (_ignoreChangedEvent) return;

            if (e.PropertyName == _propertyName) _controller.OnModelModified();
        }

        public object GetValue()
        {
            if (_boundTo == null) return BinderNotBound.Value;

            PropertyInfo property = _boundToType.GetProperty(_propertyName);

            if (property == null) return BinderMissingProperty.Value;

            return property.GetValue(_boundTo, null);
        }

        public void SetValue(object value)
        {
            if (_boundTo == null) return;

            PropertyInfo property = _boundToType.GetProperty(_propertyName);

            if (property == null) return;

            try
            {
                _ignoreChangedEvent = true;

                property.SetValue(_boundTo, value, null);
            }
            finally
            {
                _ignoreChangedEvent = false;
            }
        }
    }
}
